Car sounds rough after fueling...

Julie1979

Suspended / Banned
Messages
1,411
Name
Julie
Edit My Images
No
I filled my car up at a Morrisons garage yesterday. Normally I use Tesco but I completely forgot to fill up when I was there so I nipped to Morrisons which was closest to home. Today it sounded quite rough, I called the filling station and they said there was no problem as nobody else had contacted them.

What would you do? I just sounds rough, there are no performance issues.

Would you run the tank right down and refill or should I maybe refill when I get down to around half full (or half empty) I do 2 x 10 mile round trips on a normal day so fairly short trips. I expect to be at half way early next week after doing a fair bit of driving today. It's a Mini Countryman so a fairly small fuel tank. The car is only 16 months old, i've owned it 6 weeks and it's never sounded rough when accelerating.

I'm currently thinking fuel but maybe there's something else?
 
i'd assume fuel and get the tank drained. If the pumps were different colours than you were used to it could have been a simple case of putting wrong fuel in. If not it could be water in the fuel which would be the supermarkets fault. When you've discounted fuel it'll then be easier to chase down what is actually wrong.
 
Sounding rough is going to be impossible to diagnose over the internet without a lot more information. If you're worried, get it looked at.
 
Definitely the right fuel. I quadruple check after putting petrol in my Audi a few years ago. I was hoping it wouldn't require drained but we can stick it it in a jerry can while we discount it I guess.
 
When you say sounds quite rough, it suggests you are just imagining a problem because you didn't fill up at the usual place ... I was watching a documentary earlier about how sexism is still prevalent in our society, so i'll say no more :D
 
Most likely water in the fuel. There have been a few reports of this happening at various supermarkets.


Steve.
 
When you say sounds quite rough, it suggests you are just imagining a problem because you didn't fill up at the usual place ... I was watching a documentary earlier about how sexism is still prevalent in our society, so i'll say no more :D

My husband noticed it too so we can discount that :)
 
After reading a few too many horror stories of £3+K bills via google I think i'll get it back to mini. The bluetooth has been playing up but it didn't seem worth the 40 mile round trip to get it seen to.
 
Maybe start using ESSO or BP next time. Supermarkets don't add additives and poor maintenance may lead to higher water content or much worse - some sediments. You can't have too much water in petrol or diesel - the stuff is simply immiscible. Maybe 1-2% max and that won't kill an engine. And there is fuel filter to deal with all kinds of rubbish. I'd think about replacing it in the next planned service.
Also morissons sells you biodiesel so by definition my car is not supposed to use their fuel if we follow the manual. I imagine yours will be the same. Depending on engine your car may even require premium grade fuels.
 
Also morissons sells you biodiesel so by definition my car is not supposed to use their fuel if we follow the manual. I imagine yours will be the same. Depending on engine your car may even require premium grade fuels.
All diesel is biodiesel, it's just the percentage difference between supermarket fuels, some cheaper brand fuel stations and the bigger brands. The cars ecu should adapt to running on the higher content biodiesel but it can take some time. Higher content biodiesel will be less responsive than the lower content biodiesel.
 
I wouldn't assume "fuel" first off. You've owned the car for six weeks. It's quite possible something's gone wrong - it can happen to a 16 month old car - or it's equally possible it's a characteristic you haven't noticed before, possibly related to the colder weather. If it worries you, I'd recommend diluting the fuel with several top ups from a source you trust and see if the roughness changes.
 
I wouldn't assume "fuel" first off. You've owned the car for six weeks. It's quite possible something's gone wrong - it can happen to a 16 month old car - or it's equally possible it's a characteristic you haven't noticed before, possibly related to the colder weather. If it worries you, I'd recommend diluting the fuel with several top ups from a source you trust and see if the roughness changes.
Supermarket fuel should be avoided. The low quality additives packages and modern engines aren't a good mix. My friend runs a Mercedes specialist. The ones that need new injectors seem to have a theme of being ran on supermarket fuel.
 
I always fill up at supermarkets, usually Asda, but sometimes Tesco or Morrisons (which ever's cheapest) and never had an issue.
I've done almost 65000 miles in the last three years and seen great economy and good performance with standard diesel from the supermarkets - and saved myself quite a few bob as well.

I think it's much more likely an issue with the car than the fuel.
 
I always fill up at supermarkets, usually Asda, but sometimes Tesco or Morrisons (which ever's cheapest) and never had an issue.
I've done almost 65000 miles in the last three years and seen great economy and good performance with standard diesel from the supermarkets - and saved myself quite a few bob as well.

I think it's much more likely an issue with the car than the fuel.
As I wrote earlier the ecu will adapt the engine to the lower grade fuels, unless the fuel is of extremely poor quality. The fact that your engine has run on nothing but supermarket fuel means it's used to it and knows no better. However some people have encountered problems running their cars on supermarket fuel to the point that the car needs to go to a garage. On inspection, in some cases there has been evidence of a green mould like substance in the fuel system which is put down to higher bio content which comes from vegetation.
 
I think it is more likely to be a case of coincidence, there are many many many things especially on modern diesels that can cause such issues, to instantly blame the supermarket fuel is jumping the gun a bit.

as for supermarket fuel being of poor quality, it's just absurd people go around saying this, it could happen at any petrol station, morrisons and Tesco etc do not make there own fuel, and supermarket petrol is not normally much cheaper than branded equivalents, and when it is cheaper they use it as a loss leader to boost sales in the supermarket.

there are quite simply millions of people who use supermarket fuel all the time and have no such issues, I am one of them,

all my cars I have owned have always been high performance variants, and the last one I modified the whole car quite substantially most of it was custom work, and was running 300bhp from a little 1300cc engine, this I alkways ran on Tesco momentum, and the odd occasion I ran it on shell vpower and bp ultimate and it never ran or felt any different.

for a main dealer to blame poor quality fuel as the cause of breakdowns is as absurd as saying it is because you didn't use Castrol engine oil and instead you used Valvoline.

I will admit that sometimes poor quality fuel does make it into service stations, but this is the case for most service stations, not just supermarkets.
 
difficult to make a judgement here. is the car UL or DERV? I assume UL, most modern cars' ECU can adapt to fuels of varying quality, putting a small amount of diesel in a petrol car can be tolerated, but not the other way around.

Supermarket fuel? I use it most of the time - OH's Golf gets troublesome with Shell, but not Sainsburys....
 
I think it is more likely to be a case of coincidence, there are many many many things especially on modern diesels that can cause such issues, to instantly blame the supermarket fuel is jumping the gun a bit.

as for supermarket fuel being of poor quality, it's just absurd people go around saying this, it could happen at any petrol station, morrisons and Tesco etc do not make there own fuel, and supermarket petrol is not normally much cheaper than branded equivalents, and when it is cheaper they use it as a loss leader to boost sales in the supermarket.

there are quite simply millions of people who use supermarket fuel all the time and have no such issues, I am one of them,

all my cars I have owned have always been high performance variants, and the last one I modified the whole car quite substantially most of it was custom work, and was running 300bhp from a little 1300cc engine, this I alkways ran on Tesco momentum, and the odd occasion I ran it on shell vpower and bp ultimate and it never ran or felt any different.

for a main dealer to blame poor quality fuel as the cause of breakdowns is as absurd as saying it is because you didn't use Castrol engine oil and instead you used Valvoline.

I will admit that sometimes poor quality fuel does make it into service stations, but this is the case for most service stations, not just supermarkets.

no the supermarkets dont make their own fuel but it is a completely different grade (check the the british standards numbers on the pump).

you cant compare tesco momentum to regular "supersaver" unleaded.
 
Is it a diesel with a DPF? If that is trying to regenerate then that could account for a different sound to the engine.

If it does only 10 mile journeys at lowish speeds eg average under 40 all the time then a DPF equipped car is potentially unsuitable for that kind of use. They have to be blasted regularly along fast roads inspite of what manufacturers claim.
 
http://www.whatcar.com/News/Detail?pageTag=is-supermarket-diesel-inferior&articleID=217130

super market fuel being rubbish is an urban myth

as for dpf's, dpf's only regenerate when sitting at 70mph for a period longer than 15 mins, or so we are led to believe at work, cars can be put into regen mode manually by most workshops (its a scary process, as the engine revs constantly at something like 3k rpm for about an hour, and the exhaust heats up glows a bright red, and it just seems a bit scary thining its a customers car and what if it goes wrong lol, although putting it into regen mode doesn't always clear the dpf and sometimes an additive needs to be added)
 
Doesn't happen when I use Esso or BP....

they're likely different grades.

super market fuel being rubbish is an urban myth

bit of a sweeping statement.. like i say it will depend on the engine. i used to have a few cars that suffered from knocking if i ran them on anything other than shell optimax as it was at the time. but as its been said, most modern ecu will adapt to suit over time.

my current vw derv sounds like a bag of spanners on morrisons and sainsburys diesel though.
 
difficult to make a judgement here. is the car UL or DERV? I assume UL, most modern cars' ECU can adapt to fuels of varying quality, putting a small amount of diesel in a petrol car can be tolerated, but not the other way around.

Supermarket fuel? I use it most of the time - OH's Golf gets troublesome with Shell, but not Sainsburys....

Actually, that is the wrong way round - a diesel car can burn petrol. But a petrol car cannot burn diesel. Diesel is a lot more difficult to burn, you can put a fire out quite easily by throwing a bucket of diesel over it (unless it is burning very well / hot at its core.)
 
they're likely different grades.



bit of a sweeping statement.. like i say it will depend on the engine. i used to have a few cars that suffered from knocking if i ran them on anything other than shell optimax as it was at the time. but as its been said, most modern ecu will adapt to suit over time.

my current vw derv sounds like a bag of spanners on morrisons and sainsburys diesel though.

fuel has to be made to a certain standard.

high performance cars are designed to run on 97+ron, normal everyday cars are designed to run on 95 ron.

95 ron from a supermarket will run the same as 95 ron from shell,

97 ron Sainsbury's runs the same as 97 ron bp ultimate

the cleaning agents inside the fuel may be different, but the fuel will act the same in terms of performance,

cars detect what fuel you are running by how much detonation (knock) is produced, and adjusts itself, this isn't new technology it has been on fuel injected cars since the early 90's.

as for diesels

Diesel engines are fuel insensitive (what a brilliant invention) and will give an output which is a function of the fuel's calorific value unless detonation occurs. To avoid this, a minimum cetane value is required and automotive production engines are set to operate within this limit - defined by EN590.
, a change to Winter fuel will generally degrade engine output (or increase consumption for the same duty) as it has a slightly lower calorific value than Summer fuel. Simple.
Magical "lubricity" additives will not make up for a poorly designed fuel system. If the thing is any good, it will run for an adequate lifetime on any fuel which meets the engine maker's spec. A marginally designed fuel system will always be just that.
 
Last edited:
I think it is more likely to be a case of coincidence, there are many many many things especially on modern diesels that can cause such issues, to instantly blame the supermarket fuel is jumping the gun a bit.

as for supermarket fuel being of poor quality, it's just absurd people go around saying this, it could happen at any petrol station, morrisons and Tesco etc do not make there own fuel, and supermarket petrol is not normally much cheaper than branded equivalents, and when it is cheaper they use it as a loss leader to boost sales in the supermarket.

there are quite simply millions of people who use supermarket fuel all the time and have no such issues, I am one of them,

all my cars I have owned have always been high performance variants, and the last one I modified the whole car quite substantially most of it was custom work, and was running 300bhp from a little 1300cc engine, this I alkways ran on Tesco momentum, and the odd occasion I ran it on shell vpower and bp ultimate and it never ran or felt any different.

for a main dealer to blame poor quality fuel as the cause of breakdowns is as absurd as saying it is because you didn't use Castrol engine oil and instead you used Valvoline.

I will admit that sometimes poor quality fuel does make it into service stations, but this is the case for most service stations, not just supermarkets.


Having high performance cars you are not exactly likely to use cheap fuel any way. My car has a warning inside the fuel flap to use a minimum octane rated petrol and the sales brochures actually state that the power figure is only achievable on 98Ron.
Other than Tesco Momentum all supermarket fuels are the bare minimum conforming to the standard. Everything else has different levels of additives which are selected at the refineries when the lorry drivers fill their tankers.
Alot of poor running can be attributed to how much the ecu can adapt the engine timing etc to perform at it's optimum on the fuel.
 
this is one of those mac vs pc, nikon vs canon debates to be honest.

exactly its personal preference.

the only reason supermarket fuel has a bad rep is because once one Tesco fuel station had a contaminated tank, and suddenly that's its all supermarket fuel is instantly rubbish.

anyway back on topic,

to the OP before making accusations about the quality of fuel, you must first have your car checked, normally if the engine sounds rougher then there must be a performance deficiency, maybe its just a placebo effect happening, it's certainly odd,
 
the only reason supermarket fuel has a bad rep is because once one Tesco fuel station had a contaminated tank, and suddenly that's its all supermarket fuel is instantly rubbish.
disagree, ive thought badly of supermarket fuels since way before any of that. esso diesel makes my derv sound less rattly than morrisons etc.

but hey, we'll be going around in circles all day on this.
 
cleaning agents in branded fuels play a huge part in the longevity of injecots, intake manifolds, egr valves etc.

but it doesn't make the car run any different, and its only the specialised stuff like bp ultimate that has these extra additives, the standard fuels are mostly the same

a bottle of redex every couple of months or couple of fills will solve that problem
 
Last edited:
I remember reading a post like this on another forum and some one piped up that they knew supermarket fuel is different from branded with different additives because they once saw the tanker driver in tesco pouring additives into the top of his tanker when delivering.

Make me laugh out loud. Being an ADR qualified fuel tanker driver, the very thought of standing on top of the tanker pouring stuff in is like a doctor being alowed to wear flip flops and shorts in an operating theatre. It ain't gonn happen.

People, by and large are completely clueless about fuel, especially supermarket fuel.

Strange how I see Shell tankers, BP tankers and Tesco tankers all filling from the same gantry. I guess the driver gets on top after and pours a load of redex in.
 
high performance cars are designed to run on 97+ron, normal everyday cars are designed to run on 95 ron.
I can't vouch for other car manufacturers, but I see no reason for them being any different to Ford, but normal everyday engines will have been developed to run on a variety of fuel ratings, some not available in this country such as 91Ron and also the higher rated fuels, 97 and upwards.
 
I remember reading a post like this on another forum and some one piped up that they knew supermarket fuel is different from branded with different additives because they once saw the tanker driver in tesco pouring additives into the top of his tanker when delivering.

Make me laugh out loud. Being an ADR qualified fuel tanker driver, the very thought of standing on top of the tanker pouring stuff in is like a doctor being alowed to wear flip flops and shorts in an operating theatre. It ain't gonn happen.

People, by and large are completely clueless about fuel, especially supermarket fuel.

Strange how I see Shell tankers, BP tankers and Tesco tankers all filling from the same gantry. I guess the driver gets on top after and pours a load of redex in.
They may all be filled from the same gantry, but similar to how you can select the fuel you want at the forecourt pump, different mixes are selected at the gantry by the driver.
 
Back
Top